Analytical appraisal of post-concussion brain metabolism: Not elite academy but essential issue for return to play

Sports contexts are accountable for up to one-third of all TBIs, the majority of which are concussive brain injuries. Post-concussion symptoms recover spontaneously within days-weeks, but may last for much longer time, not infrequently. At the time of impact, the mechanical forces transmitted to the brain initiate a complex series of chained biochemical pathways, modifying proteins and genes expressions, mitochondrial functions, energy metabolism, oxidative/nitrosative stress. During a scarcely predictable post-trauma period, brain cells must be defined as biochemically, metabolically and genetically vulnerable. This “window of vulnerability” lasts longer than symptom clearance and it is very probably involved in the occurrence of both fatal and non-fatal second impact syndrome (SIS). Proton magnetic resonance spectroscopy (1H-MRS) can monitor brain biochemistry, by identifying and quantifying various metabolites connected to nervous cell energetic. Growing clinical evidences, from either 1H-MRS or other advanced neuroimaging techniques, clearly established that metabolic and ultrastructural concussion-mediated brain alteration persist beyond clinical and neuropsychological clearance. Data from these examinations represent a significant step forward in objectively quantifying post-concussive brain disturbances, for a safer return of athletes to play. SIS apart, the combination of longitudinal 1H-MRS information with advanced neuroimaging can be crucial to minimize the risk that recurrent injuries (causing cumulative biochemical networks impairment) may develop into chronic traumatic encephalopathy. These high-tech wealth should not be considered just as sophisticated research-related instruments, but a valid, complementary, decisive diagnostic and, above all, prognostic instrument